Creating perfect composite vortex beams with a single all-dielectric geometric metasurface

Optical vortex beam carrying orbit angular momentum has been extensively re-searched and applied recently. Among which a perfect vortex beam (PVB) has attracted much attention owing to its topological charge (TC)-irrelevant intensity profile. However, the morphology singularity, as well as implementation complexity of the PVB tie the degree of freedom for multiplexing. Herein, by introducing the concept of a composite vortex beam, we originally propose a novel kind of PVB -perfect composite vortex beam (PCVB) ??? which possesses a rosette-like intensity pattern that is exactly correlated with the TC and can be directly generated using a single all-dielectric geometric metasurface rather than bulky optical systems. We numerically simulate the broadband generation of the proposed PCVB with various TCs, sizes, and rotation angles. To further explore the potential of our design in practical applications, we demonstrated the coaxial array of the PCVBs and detected their optical angular force for manipulating nanoparticles. We believe that our fruitage may pave a desirable avenue for optical communication, information processing, and optical manipulation. (c) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

The research and application of optical vortex beams carrying orbital angular momentum have received extensive attention recently. A perfect vortex beam (PVB) has attracted attention due to its topological charge-independent intensity profile. However, the morphology singularity and complex implementation of the PVB limit its degree of freedom for multiplexing. By introducing the concept of a composite vortex beam, we propose a novel kind of PVB, called perfect composite vortex beam (PCVB), which can be directly generated using a single all-dielectric geometric metasurface rather than bulky optical systems.